The quadratic polynomial,the sum and product of whose zeroes are -3 and 2, is
Answers
Answer:
x² + 3x + 2
Step-by-step explanation:
Given,
Sum = -3
Product = 2
Let the zeroes be a and b
a + b = -3
ab = 2
so, the quadratic equation is....
x² - (a + b)x + ab
= x² - (-3)x + 2
= x² + 3x + 2
You might think how I got (x² - (a + b)x + ab) this equation
I will show you the proof if in case you dont know
Let the Quadratic equation be
ax² + bx + c = 0
Dividing whole equation by a we get
x² + (b/a)x + (c/a) = 0
Now let A and B be the zeroes of the Quadratic equation x² + (b/a)x + c/a = 0 -----1
Thus x = A and x = B
thus, factors will be (x - A) and (x - B)
(x - A)(x - B) = 0
x² - Bx - Ax + AB = 0
x² - (A + B)x + AB = 0 ------2
Now if we were to compare eq.1 and eq.2 we get
-(A + B) = b/a
A + B = -b/a
AB = c/a
Thus,
Sum of Zeroes = -b/a
Product of zeroes = c/a
Also,
x² + (b/a)x + c/a = x² - (A + B)x + AB
Hence proved
Hope you understood it........All the best